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Hypothesis Delivery of multiple payloads using the same micelle is of significance to achieve multifunctional or synergistic effects. The interacting distribution of different payloads in micelles is expected to influence the loading stability and capacity. It is highly desirable to explore how intermolecular interactions affect the joint distribution of multi-payloads. Experiments Dissipative Particle Dynamics simulations were performed to probe the loading of three payloads: decane with a linear carbon chain, butylbenzene with an aromatic ring connected to carbon chain, and naphthalene with double aromatic rings, within poly(β-amino ester)-b-poly(ethylene glycol) micelles. Properties of core-shell micelles, e.g., morphological evolution, radial density distribution, mean square displacement, and contact statistics, were analyzed to reveal payloads loading stability and capacity. Explorations were extended to vesicular, multi-compartment, double helix, and layer-by-layer micelles with more complex inner structures. Findings Different payloads have their own preferred locations. Decane locates at the hydrophilic/hydrophobic interface, butylbenzene occupies both the hydrophilic/hydrophobic interface and the hydrophobic core, while naphthalene enters the hydrophobic core. More efficient delivery of multi-payloads is achieved since the competition of payloads occupying preferred locations is minimized. The fusion of micelles encapsulating different payloads suggests that specific payloads will move to their preferred positions without interfering other payloads.

This study developed an efficient and green method for isolating and purifying lignin from black liquor (BL) using deep eutectic solvents (DESs). After the short and mild process (700 W microwave-assisted, 100 °C, DES: BL 1:5 (v: v), 30 min) using optimized DES (lactic acid (LA): choline chloride (ChCl) 10:1, molar ratio), the yield and purity of lignin obtained from 100 mL BL was 1.58 g and 88.12%, respectively, which was more efficient than the results of 1.18 g and 78.54% of the conventional process. Furthermore, more than 95% of initial results were obtained after three cycles. The composition and structure of DESs and conventionally purified lignin were slightly different. The solvent costs for both processes were also evaluated, showing that the DES process has great potential to replace traditional bulky and environmentally unfriendly procedures for lignin isolation and purification and to help develop new strategies for the potential added value of lignin.

Fe-based amorphous alloy (FAA) is considered to be a new type of wastewater treatment catalyst. In this paper, the degradation performance of Fe-Nb-Cu-Si-B amorphous alloy powders to methyl orange (MO)...

Polymersomes with inhomogeneous membranes in composition and structure have generated widespread interest for the preparation of functionalized nanocarriers. We propose a simple but versatile strategy to manipulate inhomogeneous subdomains on polymersome membranes by the co-assembly of block copolymer blends with varied molecular architectures and chemistries. Both binary and ternary copolymer blends are considered to construct polymersomes, and the subdomains of the membranes are formed by controlling the difference in the flexibility and rigidity of different blocks. This difference contributes to the formation of disk-like domains (by rigid blocks) and soft domains (by flexible blocks) on the membrane. An interesting effect of this structure is that in response to external stimuli, the soft membrane domain becomes worm-like or porous to "open" the polymersome for matter exchange, while the rigid domain stays undecomposed and acts like an anchor binding all flexible copolymers. Once the external stimuli disappear, all flexible copolymers can be pulled back to restore the original polymersome morphology (

Background Increased Hcy level is an independent risk factor for coronary heart disease (CHD). It was proposed that yellow rice wine improves Hcy-induced EPCs dysfunction and inhibits the development of atherosclerotic plaques. In this study, we observed whether yellow rice wine and red wine improve the properties of homocysteine (Hcy)-induced endothelial progenitor cells (EPCs). Methods The bone marrow of rats was extracted to isolate EPCs from the bone marrow cell suspension using density-gradient centrifugation. The cells were inoculated on culture plates coated with human fibronectin (HFN), to induce mononuclear cell differentiation into EPCs. Samples were divided into 5 groups including a control group. Western blotting. and NO assays were used respectively to observe the generation of eNOS, p-eNOS and NO. MTT and transwell assays were conducted. Apoptosis and in vitro angiogenesis of EPCs were determined. Results Compared with the control group, the potential for proliferation, migration and in vitro angiogenesis of EPCs decreased significantly following Hcy intervention (P 0.05). No impact on apoptotic function of EPCs was observed (P > 0.05). Hcy significantly lowers the capacity of proliferation, migration and in vitro angiogenesis of EPCs and reduces the production of eNOS, p-eNOS and NO. Conclusion Our results showed Hcy significantly lowers the capacity of proliferation, migration and in vitro angiogenesis of EPCs and reduces the production of eNOS, p-eNOS and NO,which indicates that yellow rice wine and red wine in small doses improve the functions of EPCs.

A three-dimensional hollow NiCo2O4 structure was successfully prepared with a precipitation-hydrothermal method. A balance between magnetic and dielectric losses was achieved by using a hollow NiCo2O4 structure loaded with benzotriazole (BTA), and thus the performance of electromagnetic waves was attenuated. The minimum reflection loss value of BTA@NiCo2O4 at 16.01 GHz was −35.39 dB when the absorber thickness was 2 mm, at which the absorption bandwidth for an RL of less than −10 dB is as high as 4.64 GHz. The absorption mechanism was characterized by the synergy among interfacial polarization, multiple reflection, and dipole polarization enhancement between NiCo2O4 and BTA. Interestingly, the epoxy/BTA@NiCo2O4 coating not only exhibited an outstanding microwave absorption (MA) performance but also has excellent anticorrosion and self-healing properties, as shown by the results of electrochemical impedance spectroscopy and confocal laser scanning microscopy. This work would be very helpful to the development of novel coatings with excellent MA performance and anticorrosion and self-healing properties.

In view of the critical importance of oxygen to corrosion evolution, to starve corrosion via depleting oxygen in coatings is a promising strategy. In this work, a novel nanocatalytic anticorrosion concept is proposed to design new coating with outstanding corrosion resistance. Different from the passive barrier of traditional coatings and self-repair after corrosion of current stimuli-feedback coatings, such coating could spontaneously eliminate internal diffused oxygen and greatly suppress the corrosion process. As a proof of concept, single-atom Fe-N-C electrocatalyst with isolated FeN

Dissipative particle dynamics (DPD) simulations were applied to investigate the effect of SiO2 nanoparticles (SNPs) modified with different tertiary amine chain length and concentration on O/W emulsion properties, the influence mechanism was also revealed from the molecular level. On this basis, the influence of the modified SNPs volume fraction in the emulsion system was studied. The results showed that with the increase number of tertiary amine chain alkyl carbon, the stability of the original emulsion system was first enhanced and then weakened while the responsiveness of the protonated emulsion system was first weakened and then slightly enhanced, the number of tertiary amine chains modified on SNPs has the same influence rule on emulsion performance, which was determined by the hydrophobicity of modified SNPs. In addition, with the increase of the modified SNPs volume fraction in the emulsion system, the stability of the emulsion is gradually enhanced. However, when the volume fraction of SiO2 exceeds 3%, the amplitude of stability enhancement decreases. The increase in the interaction energy between oil droplets in the equilibrium process is caused by emulsion fusion, which in turn is affected by SNPs. The repulsive force between oil and water is greater than that between two oil drops, which is the reason for the oil drop fusion. The presence of SNPs can reduce the repulsive force between oil and water to different degrees, thus slowing down the fusion of emulsion.

Self-healing materials with high self-healing efficiency and excellent mechanical properties are desired for practical applications. Herein, imine-based epoxy composites enhanced by surface modified halloysite nanotubes (SiUr@HNTs) were fabricated. According to DSC curves, epoxy composites with 3 wt% of SiUr@HNTs have an excellent cure state. The addition of 3 wt% of SiUr@HNTs not only gives a certain fluidity to the composites to improve the self-healing performance (the tensile strength can restore to 7.10 MPa and the self-healing efficiency can reach 99.8%), but SiUr@HNTs can also be used as a mechanical enhancer to enhance the mechanical properties (the tensile strength increases from 5.16 MPa to 7.12 MPa). In addition, the epoxy composites can withstand large stretching and a weight of more than 400 g after ex situ self-healing. Besides, the epoxy composites have great thermal stability and solvent resistance. In general, this work proposed a method to improve the mechanical properties of self-healing materials, which is promising in the development of high-strength self-healing composite materials.

The exfoliation corrosion behaviour of 2024 aluminium alloy was investigated through exfoliation corrosion test, together with synchrotron radiation X-ray computed tomography (SR-CT) to achieve the 3D segmentation of precipitated phases, cracks and corrosion products. The results demonstrate that aging treatment has a significant effect on the distribution of the precipitated phases in the 2024-T4 aluminium alloy, and the precipitated phases continuously distributed along the grain boundary would lead to intergranular corrosion (IGC) which is easily evolved into exfoliation corrosion. In the 2024-T2 aluminium alloy, the longest crack was found to locate at the boundary between the inner grains structure and outer peripheral coarse grain (PCG) structure, which indicates that the corrosion is attributed to electrochemical property difference of two structures.

Experiment and molecular dynamics simulation were carried out to study the tunable stability of oil-containing SDS-stabilized Nitrogen-in-water foam. The experimental results show that the foam stability could be tuned by the concentrations of SDS and modified SiO2 nanoparticles. In the foam systems with a low SDS concentration (0.2 wt.%), the foams show poor stability and the foam stability was almost not affected by the addition of modified SiO2 nanoparticles. The foam stability was greatly improved at moderate SDS concentration (0.5 wt.%), it enhanced first and then weakened with the increase of modified SiO2 concentration, and the half-life time achieved a maximum value of 1292 s at 0.05 wt.% modified SiO2. However, at high SDS concentration (0.8 wt.%), the foam stability was pretty good except for when the modified SiO2 concentration is too high (>0.2 wt.%). The microscopic mechanism was obtained by investigating the structural and dynamic properties of the foam film. The simulation work showed consistent results of foam stability with the experimental results. Moreover, it also revealed that the concentration and configuration of SDS will affect its interaction with SiO2 and oil molecule, which is critical to foam stability.

The designability and adjustability of the pore structure are vital advantages of metal–organic framework (MOF) materials for separation. Their exploration in the field of membrane separation is still inadequate, especially for the regulation of the pore environment based on the inorganic secondary building unit (SBU). In this work, we have studied the effect of the pore environment regulated by the SBU on the gas separation performance of MOF membranes for the first time. The Fe3(μ3-O)(CH3COO)6 SBU of the parent framework (soc-MOF, a stable microporous Fe-MOF) was in situ modified with imidazole (IM) molecules to construct the soc-MOF-IM polycrystalline membrane. The exact location of the incorporated IM and the narrowed pore size are observed based on the determined crystal structure. The gas solubility, diffusivity and separation performance of the two membranes are evaluated. Compared to the soc-MOF membrane with a H2/CO2 selectivity of 6, the soc-MOF-IM polycrystalline membrane possesses a significantly enhanced H2/CO2 selectivity (48), which is mainly attributed to the triggered molecular sieving effect. Thanks to the facile introduction of functional molecules and precise adjustment of the pore environment, SBU modification can be a powerful strategy to improve the separation performance of MOF membranes.

Conventional polyamide (PA) nanofiltration (NF) membranes can readily adsorb aromatic compounds, such as endocrine disrupting compounds (EDCs). Therefore, these substances can easily be transported across the membrane by solution-diffusion, resulting in a poor EDC-rejection. In this work, a novel thin film nanocomposite (TFN) membrane was fabricated by incorporating covalent organic frameworks (COFs) into the PA layer via an interfacial polymerization reaction. COFs with functional groups can provide abundant active binding sites for highly efficient EDC-capture. The rejection of the optimal TFN-COF membrane for bisphenol A, bisphenol AF, and sodium 2-biphenylate was 98.3%, 99.1%, and 99.3%, respectively, which was much higher than of the rejection of the pristine NF-membrane (82.4%, 95.5%, and 96.4%, respectively). Additionally, the TFN-COF membrane could be regenerated fast and efficiently by washing with ethanol for some minutes. COF nanofillers with porous structures provide additional water channels, making it possible to overcome the permeability-selectivity trade-off of NF membranes. The water permeance (17.1 L m

Density functional theory was used to investigate the anticorrosion mechanism of Cr-doped nickel-base alloy in Br/O environment. The adsorption properties including adsorption energy, bond length a...

Molecular dynamics simulations are used to investigate the effects of temperature, strain rate and molecule length on the deformation of graphene/polyethylene composites. At higher temperature, the host molecules move easily to fit the strain during the deformation. When the strain rate is lower, atoms in the composite model are more relaxed to fit the strain, thus the yield stress of the composite model is smaller than that at a higher strain rate. Due to the longer the length of molecules, the relative movement between molecules is more difficult with the increase of the strain, resulting in a larger yield stress.

Defects in metal–organic frameworks (MOFs) can play an important role in the development of MOFs as promising reverse osmosis (RO) membranes for water desalination. By employing molecular dynamics ...

Pseudomorphic conversion of metal-organic frameworks (MOFs) enables the fabrication of nanomaterials with well-defined porosities and morphologies for enhanced performances. However, the commonly reported calcination strategy usually requires high temperature to pyrolyze MOF particles and often results in uncontrolled growth of nanomaterials. Herein, we report the controlled alkaline hydrolysis of MOFs to produce layered double hydroxide (LDH) while maintaining the porosity and morphology of MOF particles. The preformed trinuclear M3(μ3-OH) (M = Ni2+ and Co2+) clusters in MOFs were demonstrated to be critical for the pseudomorphic transformation process. An isotopic tracing experiment revealed that the 18O-labeled M3(μ3-18OH) participated in the structural assembly of LDH, which avoided the leaching of metal cations and the subsequent uncontrolled growth of hydroxides. The resulting LDHs maintain the spherical morphology of MOF templates and possess a hierarchical porous structure with high surface area (BET surface area up to 201 m2·g-1), which is suitable for supercapacitor applications. As supercapacitor electrodes, the optimized LDH with the Ni:Co molar ratio of 7:3 shows a high specific capacitance (1652 F·g-1 at 1 A·g-1) and decent cycling performance, retaining almost 100% after 2000 cycles. Furthermore, the hydrolysis method allows the recycling of organic ligands and large-scale synthesis of LDH materials.

Dissipative particle dynamics (DPD) simulations were applied to investigate the solution self-assembly and pH-responsive behavior of hydrophobic DCPD (dicyclopentadiene)-loaded microcapsules from triblock copolymers poly (1,2-ethanediol, homopolymer-b-2-Diethylaminoethylmethacrylate-b-methyl methacrylate) (PEG- b -PDMAEMA- b -PMMA). Results indicate that micelles with longer hydrophilic PEG blocks and shorter hydrophobic PMMA blocks were in favor of encapsulating hydrophobic DCPD. Cross-linking at the core/shell interface generates a chemically bonded network structure in the micelle and leads to a significant decrease of their thermodynamic mobility (i.e., the increase of stability). Both non cross-linked and cross-linked micelles show a good pH-responsive behavior. In particular, cross-linked micelles still have the ability to carry DCPD due to the incomplete dispersion even completely protonation of PDMAEMA, which indicates that the cross-linked micelles could be expected to realize the slow release of encapsulated DCPD agent.

Cracking of an oil inlet pipe in an electrohydraulic governing system was detected and analyzed to determine its failure mechanism. Microscopic analysis methods, such as the scanning electron microscopy and energy-dispersive X-ray spectrum, were applied to obtain the effective information. Visual and micro-examination showed that the pipe suffered a brittle cracking at the elbow part. Corrosion pits and branched cracks had formed in the outer surface of the pipe. The element of chlorine was detected both in the corrosion pits and the corrosion products inside the cracks. In addition, the cracks were found initiating from the bottom of the corrosion pit. Transgranular cracking feature was identified for the cracks. All the collected evidences suggested that the EH oil pipe fractured due to the combination of a chloride pitting corrosion and a stress corrosion cracking failure.

Frequent oil spills pose severe damages to the marine ecosystems and result in hazardous fires when the spilled oil is ignited. Developing high-performance, flame-retardant absorbent materials for large-scale water treatment is therefore urgently needed. Herein, we report an efficient post-synthetic silylation process to achieve a porous covalent-organic framework (COF), denoted as [CF3] − COF. The absorption capacity of oils and organic solvents in [CF3] − COF was explored by experimental measurements with the absorption mechanism illuminated by molecular simulations. The prepared [CF3] − COF powders were further loaded into melamine sponge to yield a highly hydrophobic absorbent denoted as [CF3] − COF@sponge, which was demonstrated to effectively remove oils/organic solvents with outstanding stability and excellent flame retardancy. Moreover, an oil-collecting apparatus was designed to continuously separate oils/organic solvents from water. The rapid recovery of oils/organic solvents from water using this device proves the great promise of [CF3] − COF@sponge in water treatment.

A three-dimensional hollow NiCo

The separation of ethylene (C2 H4 ) from a mixture of ethane (C2 H6 ), ethylene (C2 H4 ), and acetylene (C2 H2 ) at normal temperature and pressure is a significant challenge. The sieving effect of pores is powerless due to the similar molecular size and kinetic diameter of these molecules. We report a new modification method based on a stable ftw topological Zr-MOF platform (MOF-525). Introduction of a cyclopentadiene cobalt functional group led to new ftw-type MOFs materials (UPC-612 and UPC-613), which increase the host-guest interaction and achieve efficient ethylene purification from the mixture of hydrocarbon gases. The high performance of UPC-612 and UPC-613 for C2 H2 /C2 H4 /C2 H6 separation has been verified by gas sorption isotherms, density functional theory (DFT), and experimentally determined breakthrough curves. This work provides a one-step separation of the ternary gas mixture and can further serve as a blueprint for the design and construction of function-oriented porous structures for such applications.